Are plants used for skin care in South Africa fully explored?

No AbstractUniversity of Pretoria, and National Research Foundation, South Africahttp://www.elsevier.com/locate/jethpharmhb201

Antibacterial and anti-inflammatory effects of Syzygium jambos L. (Alston) and isolated compounds on acne vulgaris

Acne vulgaris is a chronic skin disorder leading to inflammation as a result of the production of reactive oxygen species due to the active involvement of Propionibacterium acnes (P. acnes) in the infection site of the skin. The current study was designed to assess the potential of the leaf extract of Syzygium jambos L. (Alston) and its compounds for antibacterial and anti-inflammatory activity against the pathogenic P. acnes. The broth dilution method was used to assess the antibacterial activity. The cytotoxicity investigation on mouse melanocyte (B16-F10) and human leukemic monocyte lymphoma (U937) cells was done using sodium 3’-[1-(phenyl amino-carbonyl)-3,4-tetrazolium]-bis-[4-methoxy-6-nitrobenzene sulfonic acid hydrate (XTT) reagent. The non-toxic concentrations of the samples was investigated for the suppression of cytokines interleukin 8 (IL 8) and tumour necrosis factor (TNF α) by testing the supernatants in the co-culture of the human U937 cells and heat killed P. acnes using enzyme immunoassay kits (ELISA). The statistical analysis was done using the Graph Pad Prism 4 program

The potential of leucosidea sericea against propionibacterium acnes

The present study reports on the potential of Leucosidea sericea addressing acne vulgaris. Four known compounds namely phytol acetate, triacontanol, phytol and alpha kosin and one new compound namely, (E)-3,7,11,15-tetramethylheptadec-2-ene-1,17-diol have been isolated for the first time from this plant. The ethanol extract of leaves and one of the isolated compounds, alpha kosin exhibited significant minimum inhibitory concentration (with MIC values 15.7 μg/mL and 1.9 μg/mL, respectively) against acne inducing bacteria, Propionibacterium acnes. Moreover, the transmission electron micrographs showed the efflux of intracellular content of the cells of P. acnes caused by plant extract and alpha kosin. The ethanol extract of L. sericea exhibited significant anti-inflammatory activity by suppressing interleukin 8 (IL 8) and tumour necrosis factor (TNF α) in coculture of human U937 cells and heat killed P. acnes at concentrations of 25.0, 12.5 and 6.2 μg/mL

Investigation towards propagation and cosmeceutical application of Athrixia phylicoides DC

The multitude of ailments related to human health has become a worldwide open challenge for scholars waged in the field of drug development. Plants have always been a gifted source of alternative medicine for countless disorders. The bush tea (Athrixia phylicoides DC.) is a South African indigenous plant with a diverse range of medicinal properties including cosmetic and antimicrobial properties. This plant has been used in different local communities to treat various ailments. Further, in rural areas it is popularly used as tea by the native people of South Africa. The present study was carried out to evaluate the effects of altered exogenous growth regulators in cutting production of bush tea in two dissimilar seasons. Based on the plant’s traditional usage in cosmetics, the tyrosinase inhibition and antimicrobial potential against the strain Propionibacterium acnes were also investigated. In the propagation study, Indole-3-butyric acid (IBA) was found to have the highest rooting and sprouting percentage during spring, while 1-Naphthalene acetic acid (NAA) was found to promote the highest sprouting and rooting percentage during autumn. Both NAA and IBA improved the number of roots produced compared to that of the control, although not significantly. The addition of exogenous growth regulators is beneficial to obtain significantly more roots per cutting and increase the cutting production of A. phylicoides but did not affect the number of leaves. Although the tyrosinase inhibitory activity was found to be higher in plants from spring as compared to the other seasons it did not compare with the positive control.The National Research Foundationhttp://www.elsevier.com/locate/sajb2018-09-30hj2017Plant Production and Soil Scienc

Antibacterial and anti-inflammatory effects of Syzygium jambos L. (Alston) and isolated compounds on acne vulgaris

BACKGROUND: Acne vulgaris is a chronic skin disorder leading to inflammation as a result of the production of reactive oxygen species due to the active involvement of Propionibacterium acnes (P. acnes) in the infection site of the skin. The current study was designed to assess the potential of the leaf extract of Syzygium jambos L. (Alston) and its compounds for antibacterial and anti-inflammatory activity against the pathogenic P. acnes. METHODS: The broth dilution method was used to assess the antibacterial activity. The cytotoxicity investigation on mouse melanocyte (B16-F10) and human leukemic monocyte lymphoma (U937) cells was done using sodium 3’-[1-(phenyl amino-carbonyl)-3,4-tetrazolium]-bis-[4-methoxy-6-nitrobenzene sulfonic acid hydrate (XTT) reagent. The non-toxic concentrations of the samples was investigated for the suppression of cytokines interleukin 8 (IL 8) and tumour necrosis factor (TNF α) by testing the supernatants in the co-culture of the human U937 cells and heat killed P. acnes using enzyme immunoassay kits (ELISA). The statistical analysis was done using the Graph Pad Prism 4 program. RESULTS: Bioassay guided isolation of ethanol extract of the leaves of S. jambos led to the isolation of three known compounds namely; squalene, an anacardic acid analogue and ursolic acid which are reported for the first time from this plant. The ethanol extract of S. jambos and one of the isolated compound namely, anacardic acid analogue were able to inhibit the growth of P. acnes with a noteworthy minimum inhibitory concentration (MIC) value of 31.3 and 7.9 μg/ml, respectively. The ethanol extract and three commercially acquired compounds namely; myricetin, myricitrin, gallic acid exhibited significant antioxidant activity with fifty percent inhibitory concentration (IC50) ranging between 0.8-1.9 μg/ml which was comparable to that of vitamin C, the reference antioxidant agent. The plant extract, compounds ursolic acid and myricitrin (commercially acquired) significantly inhibited the release of inflammatory cytokines IL 8 and TNF α by suppressing them by 74 - 99%. TEM micrographs showed the lethal effects of selected samples against P. acnes. CONCLUSIONS: The interesting antibacterial, antioxidant and anti-inflammatory effects of S. jambos shown in the present study warrant its further investigation in clinical studies for a possible alternative anti-acne agent.University of Pretoria and National Research Foundationhttp://www.biomedcentral.com/bmccomplementalternmedam201

In vitro and in vivo activity of Myrsine africana on elastase inhibition and anti-wrinkle activity

BACKGROUND : Myrsine africana (MA) is a plant traditionally used in South Africa to treat various diseases. OBJECTIVE : The ethanolic extract of MA, was used for in vitro and in vivo studies to determine its elastase inhibitory activity. MATERIALS AND METHODS : MA and its isolated compound, myrsinoside B, were tested in vitro for their elastase inhibitory activity. The MA extract was also evaluated for mutagenicity using two strains of Salmonella typhimurium (TA 98 and TA 100), microbial count, metal analysis, and stability. In vivo studies included irritancy and wrinkle reduction trials using Visioscan and Visioface. RESULTS : The leaf extract showed good elastase inhibition with a 50% inhibitory concentration (IC50) of 28.04 µg/ml. Myrsinoside B inhibited the elastase enzyme at an IC50 of 4.68 ± 0.34 μg/ml. No colony growth observed during mutagenicity studies and it was concluded that MA ethanolic extract is a nonmutagen. MA extract was found to be a nonirritant during the patch test clinical trial. MA was found to contain negligible amounts of microorganisms and heavy metals. Gel cream containing MA crude extract was found to be stable for 2 years when kept at temperatures below 30°C. In clinical trials (in vivo), it was found that the test product containing 5% ethanolic extract of MA was effective in reducing wrinkles after application 2 times a day for 14 days and 28 days compared to the placebo aqueous cream. CONCLUSION : MA is effective in reducing the appearance of wrinkles.http://www.phcog.comam2018Plant Production and Soil Scienc

Natural products as leads to potential mosquitocides

Mosquitoes are the crucial vectors for a number of mosquito-borne infectious diseases i.e. dengue, yellow fever, chikungunya, malaria, Rift Valley fever, elephantiasis, Japanese Encephalitis, and Murray Valley encephalitis etc. Besides, they also transmit numerous arboviruses (arthropod-borne viruses) for example West Nile virus, Saint Louis encephalitis virus, Eastern equine encephalomyelitis virus, Everglades virus, Highlands J virus, and La Crosse Encephalitis virus. The emergence of widespread insecticide resistance and the potential environmental issues associated with some synthetic insecticides (such as DDT) has indicated that additional approaches to control the proliferation of mosquito population would be an urgent priority research. The present review highlights some natural product mosquitocides that are target-specific, biodegradable, environmentally safe, and botanicals in origin.Department of Plant Science, University of Pretoria, South Africa, Department of Chemistry, Banaras Hindu University,India and National Research Foundation.http://link.springer.com/journal/11101hb201

The effect of Helichrysum odoratissimum (L.) sweet on cancer cell proliferation and cytokine production

The cytotoxicity of Helichrysum odoratissimum against human epidermoid carcinoma (A431), malignant melanoma (A375), cervical epithelial carcinoma (HeLa) and human embryonic kidney (HEK-293) cells was investigated. The cytokine production and antioxidant activity was also determined. H odoratissimum was selected based on its traditional usage as a dressing for wounds. In this study the cytotoxicity was performed on skin and cervical cancer which are associated with the presence of wounds. H. odoratissimum showed inhibitory activity against A431 cells, with a fifty percent inhibitory concentration (IC50) of 15.5±0.2 μg/ml, and a high DPPH inhibition with an IC50 of 5.13±0.07 μg/ml. A431 cells treated with the extract showed an increase in morphological characteristics associated with apoptosis. The extract induced IL-12 in U937 cells and inhibited IL-8 at the tested concentrations, with the highest levels being 12.4±7 pg/ml and 103±6.1 pg/ml respectively. IL-2 was inhibited by 56 % and 52 % in naive and PHA induced murine splenocytes respectively. Furthermore, 2 lipophilic fractions and 3 compounds were isolated from the extract. The lipophilic fractions showed relative cytotoxicity on A431 cells with IC50 values of 175±13.5 μg/ml and 61.3±0.16 μg/ml. The extract showed significant hepatoprotection at 25 μg/ml on HepG2 cells exposed to D-Galactosamine. This is the first report of the activity of H. odoratissimum ethanolic leaf stem extract on A431, A375, HeLa and HEK-293 cell lines as well as the isolation of two promising lipophilic fractions.The University of Pretoria, the National Research Foundation and the Department of Science and Technology.http://ijppr.comam2018Plant Production and Soil Scienc

Alkaloids from aerial parts of Annona senegalensis against Streptococcus mutans

Antimicrobial potential of medicinal plants have been explored extensively these days. This study was carried out to evaluate the antibacterial potential from aerial parts of plant, called ‘Annona senegalensis’ and its constituents. Bioassay guided fractionation led to the isolation of four metabolites, (+)-catechin (1), (−)-anonaine (2), (−)-asimilobine (3) and (+)-nornantenine (4). This is the first report on the isolation of compounds 1, 3 and 4 from this plant. Compounds 2 and 4 showed good activity, whereas 1 and 3 displayed weak inhibition against Streptococcus mutans (ATCC 25175). The results showed that compound 2 and 3 showed significant activity with a minimum inhibition concentration (MIC) of 0.12 and 0.25 mg/mL, respectively. The present study reports for the first time the antibacterial activity of the extract of A. senegalensis and its constituents. As S. mutans is a rather resistant bacteria, the MIC obtained during the present study is significant. Antibacterial potential of alkaloids isolated from Annona senegalensis.The South African Agency for Science and Technology Advancement [grant number N00117], the University of Pretoria and the National Research Foundation (NRF).http://www.tandfonline.com/loi/gnpl202017-12-31hb2017Plant Production and Soil Scienc

Extract from Ceratonia siliqua exhibits depigmentation properties

Skin hyper-pigmentation is a condition initiated by the overproduction of melanin existing in the melanocytes. Melanin pigment is responsible for the colour of skin in humans. It is formed through a series of oxidative reactions involving the amino acid tyrosine in the presence of the key enzyme tyrosinase. In continuation with our efforts to identify tyrosinase inhibitors from plants sources, the methanol extract from leaf, bark and fruit of Ceratonia siliqua were screened for tyrosinase inhibition and diphenolase activity. The bark extract exhibited significant inhibition on mushroom tyrosinase using L-tyrosine as a substrate and showed diphenolase activity. The extract further significantly inhibited tyrosinase mRNA levels in B16-F10 mouse melanocytes. Bioassay-guided fractionation led to the isolation of six compounds. Compounds (-)-epicatechin-3-O-gallate, 1,2,3,6-tetra-O-galloyl-ß-D-glucose and Gallocatechin-3-O-gallate showed tyrosinase inhibitions with the IC50 values of 27.52, 83.30 and 28.30 μg/mL, respectively. These compounds also exhibited L-DOPA activities with IC50 values of >200, 150 and 200 μg/mL, respectively. A clinical study was conducted using 20 volunteers in a patch testing trial for irritancy potential and skin depigmentation. The clinical results showed the sample to be non-irritant with irritancy potential of -34.21 and depigmentation trial showed an improvement in the even skin tone of UV induced pigmentation at 3% after 28 days of application.University of Pretoria and National Research Foundation (NRF).http://onlinelibrary.wiley.com/journal/10.1002/(ISSN)1099-15732016-11-30hb2016GeneticsPlant Scienc